Kelly driver assembly



Patented Dec. 29, 1942 KELLY DRIVER ASSEMBLY David M. Smith, Houston,

Tex., assignor to Emsco Derrick & Equipment Company, Los Angeles,Calif., a corporation of California 8 Claims.

This invention relates to rotary well drilling equipment, and relates inparticular to an attachment for a rotary machine through which rotationmay be transmitted to a string of drill pipe used in a drillingoperation.

7 The now standard method of rotating a string of drill pipe in a welluses a Kelly bar at the upper end of the string of drill pipe ofpolygonal crosssection extending through a similar polygonal opening ina part carried by the table of the rotary machine. The rotation of thetable is accordingly carried directly to the Kelly bar, with the resultthat the pipe string, of which the Kelly bar forms a part, is rotated.In the rotary table there is normally a master bushing providing avertical opening through which a string of pipe may be extended. Thismaster bushing has a tapered seat arranged to receive slips by which togrip and support a pipe which extends through the master bushing.

An object of the present invention is to provide a Kelly driver whichmay be connected to the table of the rotary machine without necessity ofremoving the master bushing from the opening of the table, and which hasno part engaging the master bushing so as to wear the master bushing,and cause wear between the master bushing and the walls of the tableopening in which the master bushing rests.

A further object of the invention is to provide 9 2. Kelly driver foruse with the table of a rotary machine which Kelly driver permits use ofa master bushing in the opening of the table, which master bushing hasits upper surface flush with the top surface of the table. remains inplace in the opening of the table during the driving of the string ofdrill pipe, and in event that holding of the drill pipe in raisedposition becomes necessary, this may be accomplished merely by raisingthe kelly which will in turn lift the Kelly driver from the upper faceof the table, and bring the upper section of the drill pipe into aposition projecting through the opening of the master bushing, whereuponthe slips may be immediately placed in the resident master bushing.There is, accordingly, no delay occasioned by the necessity of placing amaster bushing in the opening of the table, and the upper end of theopening formed by the seat of the master bushing is exposed at the uppersurface of the table, facilitating the ready placing of the slips in themaster bushing, since the shoulder defining the upper extremity of theopening in the master bushing is plainly visible in the plane of theupper surface Th master bushing 1 of the table and is not ofisetdownwardly within the opening of the table.

A further object of the invention is to provide a Kelly drivercooperating with the table of a rotary machine in such manner that wearon the gears and bearings of the rotary table and shock applied throughthe rotary table to the drill stem are minimized. During the drillingoperation the rotary table is driven through a pinion gear which drivesa ring gear secured to the table. Very often heavy vibration istransmitted from the cutting zone at the bottom of the hole through thedrill pipe to the rotary table. Also the play existing between the Kellydrive bushing and the Kelly bar results in severe jolts being applied tothe drill stem by the rotary table. The present invention providesbetween the Kelly driver and the rotary table a shock absorbing meanswhich will minimize the transmission of shocks and vibration to and fromthe table and drill pipe, thereby reducing the severity of operatingconditions which tend to cause crystallization of drill pipe, toolparts, and gear and bearing parts in the rotary machine.

A further object of the invention is to provide a Kelly driver havingmeans for driving interengagement between the body of the driver and thetable, and also having means for automatically bringing theinterengaging parts into alignment. This is an important element of theinvention. In many instances there may be four to seven thousand feet ofdrill pipe hanging from the kelly, making it difficult to bring thecooperating parts of an ordinary Kelly driver into engagement with thetable.

An additional object is to provide in a Kelly driver, a drive pin andbushing construction that is self-conpensating for wear, and alwaysmaintains a tight fit, and furthermore, has readily re-v placeableparts.

Other objects and advantages will appear and be brought out more fullyin the course of the following detailed description of the inventionchosen for illustrative purposes. It will be understood that theinvention is not limited to the details of construction hereinafterdescribed, but should be construed to cover all the modifications andchanges thereof which come within the spirit and scope of the appendedclaims.

In the drawing,

Fig. 1 is a plan view of the table portion of a rotary machineincorporating the Kelly driver of my invention.

Fig. 2 is a vertical, sectional view of the same taken along the line 22of Fig. 1.

Fig. 3 is a fragmentary view in sectional elevation showing the drivepin connection between the drill stem bushing and the table, the partsbeing in separated position.

Fig. 4 is a fragmentary sectional view showing a second form of drivepin connection between the drill stem bushings and the table, the partsbeing shown in driving relation to each other.

Fig. 5 is a fragmentary sectional view similar to Fig. 4, but showingthe cushioned drive means on the drive pin which projects downwardlyfrom the Kelly driver.

Referring to the drawing in detail, the numeral l2 represents the rotarytable of a rotary machine and has a shouldered portion l3 for engagementwith a suitable supporting bearing member, the table having a top H! anda downwardly depending skirt l5.

The table |2 has a table opening l6 concentric to the axes of rotationof the table, and the opening has a shouldered portion IT in which atable bushing I8 is suitably supported. The bushing l8 preferablycomprises two halves, I9 and 20, so that it may be installed in thetable opening while a drill pipe or stem is extending through the tableopening.

The bushing l8 has an upper shouldered portion 2| for engagement withthe upper shouldered portion H, and has a lower cylindrical portion 22which extends downwardly in opening l6 and bears against the skirt I5.The bushing |8 has an upper tapered or conical wall portion 23 forsupporting the slips, and a lower tapered or conical wall portion 24forming a guide ring surface 25. The bushing I8 has an upper surfaceportion 26 substantially level with the top M of the table I2, wherebythe slips may be positioned in the bushing with facility, since the topof the bushing |8 is within view at the top of the table at all times. AKelly drive pipe 21 is shown extending through the table opening I6 andthe bushing l8.

A Kelly driver or drill stem bushing 28 is mounted on the table l2 andhas a vertical shouldered portion 29, and a pair of base extensions 39supported on the top M, the bushing having a square shaped enlargedopening 3|, and a reduced cylindrical opening 32 through which the kelly21 extends. Openings 3| and 32 form a shouldered seat 33, and acylindrical skirt 34 extends downwardly through the bushing l8 and theguide ring 25, there being a small clearance therebetween. A linerbushing 35 is positioned in the opening 3| and is supported on theshouldered seat 33. The liner 35 is preferably composite, that is,comprises two or more parts which form a shouldered polygonal opening36, the shoulders of which engage and drive the kelly 21, which willhave a polygonal, external shape corresponding to the opening 36. Aliner locking plate 3'! is suitably secured to the top of the bushing28, such as by plurality of bolts 38, and has a drill pipe opening 39,the edge portion of which is above the bushing 35.

The table I2 is provided with drive holes or cylindrical bores 40 inwhich is positioned a metallic sleeve 4|, a rubber sleeve 42 beingpositioned in the sleeve 4|. A pin bushing 43 is positioned with therubber sleeve 42 and has a downwardly tapering bore 44. A drive pin 45is secured to each base extension 30, such as by a tapered shank portion46 positioned in a tapered bore 41 in the base extension 38, pin 45having a threaded end 48 for a lock nut 49. The pin 45 has a tapered endportion 50 corresponding to the taper of the bore 44, it beingunderstood that the axes of the bore 44 and the pin 45 are equidistantfrom the axis of rotation of the table I2.

Extensions 30 are each provided with a locking pin 5|, adapted to beinserted through an aperture 52 in the table I2, and provided with asuitable tightening nut member 53, whereby the bushing 28 is securedagainst removal from the table.

In operation the Kelly drive bushing 28 is lowered onto the table |2,pins 45 being centered for entrance into the sleeves 43 by the skirt 34as it passes into the table bushing l8, being guided by the tapered wall23 and the guide ring 25 which substantially centers the Kelly bushing,and the engagement of the pins 45 with the sleeves 43 is facilitated,which operation is otherwise often very difficult, particularly whenthere is a long string of pipe such as five or six thousand feet, whichis not an uncommon length. When the Kelly bushing is in drivingposition, as shown in Fig. 2, any shocks or impacts arising from thedrill pipe are absorbed by the rubber or other resilient sleeve 42, andare not imparted to the table 2 and its associated bearings or drivinggears, thus minimizing undue wear tending to cause crystallization ofthose parts. Also, shocks originating in the rotary machine arecushioned in their application to the drilling string.

The tapered drive pins and resiliently mounted bushing are automaticallyself-compensating for wear, and possible and occasional misalignment ofthe drive bushing and the rotary table, and insure a tight fit due tothe upward pressure of the resilient sleeve on the tapered bushing. Thedrive pin and sleeves are readily removable and replaceable after excesswear or damage from any cause, and involve a minimum of time and costtherefor.

In Fig. 4 I have shown a form of my invention in which the pin t5ainstead of being tapered at its lower end, has a cylindrical portion500. which fits into a cylindrical bore 440, of the pin bushing 430..This bushing 43a is supported within a rubber sleeve 42a which is inturn carried in the metallic sleeve 4|a. These various parts are relatedto each other in the same manner as illustrated in Figs. 1 to 3inclusive. The lower end of the pin 45a is provided with a taper 60a.which in the event of disalignment of the cylindrical portion 59a withthe bore 440 will guide the parts into alignment so that the pin may bemoved downwardly into the bore 44a.

This form of my invention includes all of the features and advantages ofthe form of the invention disclosed in Figs. 1 to 3 inclusive with theexception that there are no tapered parts whereby the bushing whichreceives the pin may be depressed downwardly. However, in this form ofthe invention the guide sleeve on the drill stem drive bushing acts as ameans for substantially centering the parts, but should there be a minormisalignment, the tapered end 60a will cause alignment between the pinand bushing.

In Fig. 5 I show the manner in which the shock absorbing connection ofmy invention may be carried on the extensions 39 of the Kelley driver28, so as to project into openings 40 in the top H of the rotary table.The extension 30 carries a pin 45' having a downwardly projectingportion 80, which is substantially cylindric and is preferably ofreduced diameter, as shown. A shock absorbing connection 8| is carriedon the downwardly projecting portion of the pin 45', such shockabsorbing connection comprising an inner metal sleeve 82, which is apressed fit on the downwardly projecting portion 80, an outer sleeve 83of hard metal and having its lower end chamfered, and an interveningcylindric body of rubber 8 3 occupying the space between the inner andouter sleeves 82 and 83. The opening it! in the table top is cylindricand is of such diameter that the outer sleeve 84 is a close sliding fittherein. In this form of the invention, the worn shock absorbing drivemember 85 may be readily replaced by removing the same from the pin 85and substituting a replacement drive member 8| therefor.

I claim as my invention:

1. In a rotary machine of the class described having a base, thecombination of: a table rotatably supported by said base, said tablehaving a top and a table opening, a table bushing mounted in saidopening and having the upper portion thereof substantially level withthe top of said table, said bushing having an internal tapered portionforming a guide ring; a drill stem drive bushing for a kelly supportedby said table and having a guide skirt portion extending into said tablebushing within said guide ring; and a shock absorbing drive connectionbetween said table and said drill stem bushing, including a drive pinand a resilient sleeve.

2. In a rotary machine of the class described having a base, thecombination of a table rotatably supported by said base, said tablehaving a top and a table opening, a table bushing mounted in saidopening and having the upper portion thereof substantially level withthe top of said table, said bushing having an internal tapered portionforming a guide ring; a drill stem drive bushing for a kelly supportedby said table and having a guide skirt portion extending into said tablebushing withinsaid guide ring; and a shock absorbing drive connectionbetween said table and said drill stem bushing, including a drive pinand a resiliently supported sleeve.

3. In a rotary machine of the class described having a base, thecombination of: a table rotatably supported by said base, said tablehaving a top and a table opening, a table bushing mounted in saidopening and having the upper portion thereof substantailly level withthe top of said table, said bushing having an internal tapered portionforming a guide ring; a drill stem drive bushing for a kelly supportedby said table and having a guide skirt portion extending into said tablebushing within said guide ring; and a shock absorbing separable driveconnection between said table and said drill stem bushing, including atapered drive pin extending from said drill stem bushing and a taperedsleeve resiliently mounted in a bore in said table.

4. In a rotary machine of the class described having a base, thecombination of: a table rotatably supported by said base, said tablehaving a top and a table opening, a table bushing mounted in saidopening and having the upper portion thereof substantially level withthe top of said table, said bushing having an internal tapered portionforming a guide ring; a drill stem drive bushing for a kelly supportedby said table and having a guide skirt portion extending into said tablebushing within said guide ring; and a separable drive connection betweensaid table and said drill stem bushing, including a drive pin and aresilient sleeve, said guide skirt and the tapered portion of said tablebushing adapted to guie said pin into said sleeve.

5. In a rotary machine of the class described having a base, thecombination of: a table rotatably supported by said base, said tablehaving a top and a table opening, a table bushing mounted in saidopening and having the upper portion thereof substantially level withthe top of said table, said bushing having an internal tapered portionforming a guide ring; a drill stem drive bushing for a kelly supportedby said table and having a guide skirt portion extending into said tablebushing within said guide ring; and a drive connection between saidtable and said drill stem bushing, including a drive pin on said drillstein drive bushing and a sleeve removably supported in said table andinto which pin is extended, there being clearance between said guideskirt and said guide ring and said drive bushing transmitting no drivingforces or weight to said table bushing.

6. In a rotary machine of the class described having a base, thecombination of: a table rotatably supported by said base, said tablehaving a top and a table opening, a table bushing mounted in saidopening and having the upper portion thereof substantially level withthe top of said table, said bushing having an internal tapered portionforming a guide ring; a drill stem drive bushing for a kelly supportedby said table and having a guide skirt portion extending into said tablebushing within said guide ring; and a shock absorbing drive connectionbetween said table and said drill stem bushing, comprising a bore insaid table, a resiliently compressable sleeve in said bore, a metallicsleeve in said compressable sleeve having a tapered bore, and a taperedpin extending from said drill stem bushmg.

7. In a rotary machine of the class described having a base, thecombination of: a table rotatably supported by said base, said tablehaving a top and a table opening, a drill stem drive bushing for a kellysupported by said table; and a shock absorbing drive connection betweensaid table and said drill stem bushing, including an interfitting drivepin and a resiliently mounted sleeve.

8. In a rotary machine of the class described having a base, thecombination of: a table rotatably supported by, said base, said tablehaving a top and a table opening, a resilient, separable driveconnection between said table and said drill stem bushing, including a,detachable tapered pin extending downwardly from said bushing, aremovable drive pin tapered bore bushing resiliently mounted in a borein the top of said table, adapted to resist downward pressure of saidpin therein.

DAVID M. SMITH.

